static int ibarrier(MPI_Comm comm, MPI_Request* request);
static int ibcast(void *buf, int count, MPI_Datatype datatype,
int root, MPI_Comm comm, MPI_Request* request);
static int ibarrier(MPI_Comm comm, MPI_Request* request);
static int ibcast(void *buf, int count, MPI_Datatype datatype,
int root, MPI_Comm comm, MPI_Request* request);